Visual tracking system and method

ABSTRACT

The present invention is directed to a user-operated spotlight system and method for lighting a performer on a stage or performance space; the user-operated spotlight system comprising a screen which displays an image of the stage and a cursor, a screen cursor positioner adapted to be operated to move the cursor on the screen, a processor connected to the screen, and, a plurality of controllable spotlights which are connected to the processor and which plurality of controllable spotlights can be moved by a user moving the cursor on the screen. The advantage of providing such a user-operated spotlight system is that a single user can operate a plurality of spotlights.

PRIORITY

This application is a continuation in part of U.S. patent applicationSer. No. 15/735,157 filed in the U.S. Patent Office on Dec. 8, 2017 as anational stage entry of PCT Patent Application No. PCT/EP2016/063225filed on Jun. 9, 2016, which claimed priority from Irish PatentApplication No. S20150171 that was filed in the Irish Patent Office onJun. 9, 2015, the entire content of these applications beingincorporated herein by reference as if fully set forth below in itsentirety and for all applicable purposes.

TECHNICAL FIELD

The present disclosure relates generally to a visual tracking system andmethod including, for example, a performance space lighting system andmethod, and more particularly, to visually tracking a source ofperformance.

BACKGROUND

In stage performances, a performer should ideally be lit from multipleangles to minimize shadows including, for example, a front angle, aleft-side angle, a right-side angle and a rear angle. Therefore, eachperformer would ideally have several lights directed towards them.

As a performer moves about the stage, these lights need to be moved inorder to continue to illuminate the performer from these various angles.Such light sources are used to illuminate a moving performer. Each lightsource, where that light source is manually operated, will require oneoperator. The operator must typically be versed in the performer'smovements and be vigilant to move the light source in coordination withthe performer's movements. When lighting a performer from four angles,for example, and using the key lighting method, four operators areneeded to illuminate each performer. As there could be severalperformers onstage at the same time, theoretically this would requiretens of operators to be positioned in areas above the stage and in areassurrounding the stage area in order to operate all of the light sources.This is not practical and oftentimes there is only enough space forapproximately six operators, even in the large theatres, who then mustdivide their time between operating different spotlights which arefocused on different performers at different times during theperformance. This is undesirable as the lighting of the performers willbe sub-optimal and therefore will impact on the overall performance. Fora number of years now fully automated spotlight systems have been known.Such a fully automated spotlight systems typically use radio frequency(RF) transmitters which are worn by each of the performers in order totriangulate a performer's position on the stage. Several RF receiverspositioned about the edges of the stage are used to calculate theperformer's approximate position on the stage by determining thestrengths of the RF signal received at the RF receivers. It will beappreciated that such systems are prone to error as the accuracy of RFtriangulation is not precise enough to capture small movements by theperformers.

Further developments of such fully automated systems have incorporatedinfrared (IR) transmitters and IR receivers in order to better determinethe position of the performers on the stage. Such IR-based systems aremore accurate than the RF-only systems but the IR-based systems stilluse the RF transmitter and receivers as the primary means of performanceposition determination. In these IR systems, the IR transmitter and IRreceiver are used as a secondary positioning system to further refinethe determination of the performer's position and the IR transmitter andreceiver system is also used as a backup in the case that the RF systemis not operating correctly.

More recently, such fully automated systems have incorporated gyroscopesinto the units that are worn by the performers in order to assist withunderstanding whether a performer has moved slightly in one direction,or if the performer has moved to a kneeling or prone position on thestage. Such small movement can be detected using the gyroscope, but theaccuracy is not perfect and there remain issues with these types ofprior art systems as discussed further hereinbelow.

Nonetheless there are still issues with these fully automated systems.For example, should a performer raised a hand to display an object, theposition of the performer on the stage will not have changed however itwould be best if the spot lighting could be moved slightly upwardly tobetter illuminate the performer's raised hand so that the audience couldclearly see the object held aloft. In other circumstances, the performermay lean slightly to the left or to the right such that the performer'shead may move out of the beam of the light source, but the performer'swaist may not have moved as they are only leaning. In this scenario, thefully automated systems may not be able to detect such movement and willnot move the lights accordingly. In situations where the performer hasonly changed position to a small degree, fully automated spotlightsystems will not have the ability to recognise or detect all of thesemovements and hence will not be able to move the spotlights in theappropriate manner so as to illuminate the performer correctly.

Furthermore, in other scenarios it is desirable to light specific areasof the stage at specific points even if there is no performer in thevicinity of that stage point at that time. With the fully automatedsystems which rely on the presence of an RF signal and/or an IR signal,it is not possible to do so. It would be necessary in such scenarios tohave a dedicated light which is directed towards that area of the stagewhich can then be switched on and switched off as needs be during theperformance. For the remaining portion of the performance this dedicatedlight would not be used which is an inefficient use of the lightingresources.

It can be seen that lighting a stage during a performance can be viewedas an art form which is best carried out by a human operator. However,to operate all of the required lights in a fully manually operatedsystem is very difficult from the point of view of having enough spacein the area surrounding the stage, and, even if it were possible toposition enough operators in the area surrounding the stage, the coststo do so would be quite high.

It is a goal of the present invention to provide a method and systemthat overcomes at least one of the above mentioned problems. Inparticular, it is desirable to provide a system which will allow theinput of a human operator to take cognisance of minor movements ofperformers on the stage and introduce a human input to the movement ofthe lights, whilst at the same time allowing a single operator tooperate a plurality of the spotlights concurrently.

SUMMARY

Certain embodiments disclosed herein, as set out in the appended claims,provide systems, methods and apparatus directed to a user-operatedspotlight system for lighting a performer on a stage or otherperformance space; the user-operated spotlight system comprising atleast one camera which points at the performance space, a screen whichdisplays an image of the performance space captured by at least onecamera and a cursor, a screen cursor positioner which can be operated tomove the cursor on the screen, a processor connected to the screen, and,a plurality of controllable spotlights which are connected to theprocessor and which plurality of controllable spotlights can be moved bya user moving the cursor on the screen.

In one embodiment there is provided a user-operated spotlight system forlighting a performer on a stage or other performance space; theuser-operated spotlight system comprising a screen which displays animage of the performance space and a cursor, a screen cursor positioneradapted to be operated to move the cursor on the screen, a processorconnected to the screen, and, a plurality of controllable spotlightswhich are connected to the processor and which plurality of controllablespotlights can be moved by a user moving the cursor on the screen.

The advantage of providing such a user-operated spotlight system is thata single user can operate a plurality of spotlights. This reduces thenumber of operators required for operating the various spotlights.Previously, manually operated spotlights required one operator for eachspotlight. As the plurality of spotlights are operated by a user, thespotlights can be operated in fashion which suits the performer's needsand introduce a human element into the movement of the lighting whichcan add to the overall performance. For example, the operator could movethe spotlights slightly to better illuminate a performer's raised hand.It will be appreciated that the system does not receive the data, andsimply converts the position of a mouse cursor mathematically into a DMXposition for the moving light or other protocol for a projector, camerapan-tilt system or scenic control system.

In a further embodiment, a pre-performance calibration stage is carriedout. In one embodiment, in order to calibrate the user-operatedspotlight system, at least two cursor positions on the screen displayingthe performance space are linked with at least two positions in theperformance space, whereby the cursor positions on the image of theperformance space relate to the actual positions on the performancespace itself. The calibration of at least two cursor positions with atleast two positions in the performance space is carried out for each ofthe plurality of spotlights, such that by pointing the cursor at aposition on the image of the performance space shown on the screen, atleast some of the plurality of spotlights will be controlled to directtheir beams towards that actual position on the performance spaceitself. It will be appreciated that any problems/characteristics of thelens can be overcome using more reference points and applying theappropriate mathematical algorithm. In other words, multiple calibrationpoints for the system can be used in the set-up.

Systems and methods incorporate a calibration process where the systemis provided with a reference position to mathematically calculate“numeric data” and convert into a protocol that a lighting fixture,motorized camera, or scenic control system can understand and in turnpoints to by moving its motors or the image as in the case of aprojector.

In a certain implementations, a camera faces the performance space inthe same direction that the audience faces the performance space. Insome implementations, the angle of the camera relative to the plane ofthe performance space is provided in the calibration performance spaceto allow the spotlights to focus at a position on the plane of theperformance space.

In certain aspects of this disclosure, a camera may be referred to asbeing a stationary camera or a moveable camera. A camera may bestationary in the sense that it is located at or above a fixed andunchanging point. A moveable camera may be equipped with motors oractuators that can adjust pan and tilt of the camera. In some instances,a moveable camera may be equipped with motors that control otheroperational aspects of the camera, including zoom and/or focus. In someinstances, a moveable camera may be equipped with motors or actuatorsthat cause the camera to move with respect to the performance area.

In a further embodiment, the screen cursor positioner is a mouse. In afurther embodiment, the screen cursor positioner is a trackball. In afurther embodiment, the screen cursor positioner is a trackpad. As auser moves the cursor on the screen using the screen cursor positioner,the spotlights are controlled to move their beams around the actualperformance space, following the movement of the cursor across theperformance space image on the screen.

In this way, a user can follow a performer around a stage or performancespace in an unplanned movement route, and by keeping the cursor over theperformer on the screen, the spotlights for illuminating that performerare controlled so as to always focus on the performer.

In a preferred embodiment, the cursor is kept over a performer's feet.In another embodiment, the user-operated spotlight system takes accountof a performer's height and adjusts the focus and direction of thespotlights, associated with that performer, from the plurality ofspotlights.

In a further embodiment, different sections of the performance space canbe accorded different heights relative to the plurality of spotlights,such that the plurality of spotlights will adjust to correctly focustogether at the correct height for these different sections of theperformance space.

In a further embodiment, the height of the camera relative to the planeof the performance space is used in the calibration stage.

In a further embodiment, the distance of the camera from a centre pointof the performance space is used in the calibration stage. The cameramay be a stationary or moveable camera.

In one embodiment a number of camera images can be stitched together toform a panoramic view of the performance space in which the performanceis taking place.

In one embodiment the system and the method may be configured toautomatically control a plurality of parameters of a moving lightautomatically. This control extends to any parameter that can adjust thelight, for example Iris, Zoom, focus and colour. This control is basedupon position in the performance space or preprogramed location thatelicit an automatic response from the system. The system and the methodcan be applied to moving cameras, moveable cameras, stationary cameras,projection systems, scenic control systems and audio systems such asmicrophones.

In one embodiment the system is configured to compensate for variationsin height of a stage structure or structure of a performance space.These items include ramps, steps and risers.

In one embodiment the system is configured with an intelligence andcontrol instructions to current follow spotlights and configure saidspotlight as a master follow spot and have any number of systems such asmoving lights, projectors, scenic controls, performer flying systems allfollow the spot of the light source.

In one embodiment the camera can be fixed and not move during operation.

In one embodiment the camera is mounted on a moving light and configuredto move in tandem with the light itself.

In one embodiment the system is configured with “centring of the head”function by providing a control in the system that spins a head and thenallows the operator to remove the non-concentricity of the rotationthereby increasing accuracy.

In one embodiment calibration of a visual tracking system may employ anapparatus that suspends a camera on a pendulum, thereby causing thecamera to hang in vertical alignment, regardless of mounting position.The pendulum suspension causes the camera to be mounted with itsvertical axis at right angles to the plane of the earth, regardless ofthe mounting position. While suspended by the pendulum, the cameraproduces an image that is aligned to the horizon. The camera may then betilted for calibration purposes, and when mounted in its final location,using a gimbal or brackets, the calibration information can be used toconfigure and adjust images produced by the camera.

In one embodiment the system can employ software code or similar toactivate or deactivate the light, camera, flying system, projector orother system that can be controlled and independently control thesesystems to carryout calibration or testing.

In one embodiment the system can control a light, camera, projector orother and independently move their axes to provide a calibration routineor system check routine for accuracy or performance.

In one embodiment the system is configured to perform compound moves ofaxes, or of systems in conjunction with each other such as lights,projection, flying and rigging systems in order to check accuracy orcheck function.

In one embodiment the system can perform an adaptive calibration, i.e.drive the light to a point and check with the operator if its locationis accurate.

In one embodiment the system can be made to automatically perform acalibration routine for one or for any and all lights, projectors,moving cameras, moveable cameras, stationary cameras, flying and riggingsystems.

In one embodiment the system is configured to work with a single videofeed and or multiple video feeds switched in and out and or multiplevideo feeds stitched into one continuous video image that may beprovided to a display screen.

In one embodiment the system can switch which lights it uses, or othersystems operated by on board processor or an auxiliary lightingprocessor.

In one embodiment the system employs an infrared or other wavelengthlight source that overcome the natural limits of an operator's eyesight.

In one embodiment the system can employ processing to place tags, or asimilar notation, saved pre-set or similar on a screen or by memoryrecall to provide a point of reference in the instance of working in ablack-out.

In one embodiment the system can be used in conjunction with videoglasses with the system.

In one embodiment integration of 3D mapping with the system isperformed.

In one embodiment there is provided an external hardware module tointerface with the system to provide a dedicated hardware control forfeatures of the software.

For example, the external hardware module can be a lump of metal thatlooks and feels like a follow spot to operate but it is a remote controlfor the mouse or lighting desk, etc.—it just gives the “feel” of afollow spot. In one embodiment the hardware module can be incorporatedinto a flight case, for example an emulator. The emulator is dimensionedto point at a monitor—moving the cursor around—but by moving the screenit's pointing at away or nearer the operator one can essentially limitthe travel of the emulator in the pan and tilt directions. This can be afeature for limiting how far an operator moves the system, can be usedto “size the ergonomics” for different operators or indeed it can beused to position an operator in a seat at the correct distance from thescreen to “smooth” out their movements.

It will be appreciated that the distance from the emulator to the screencan be set in such a way to make operation more ergonomic for theoperator.

In one embodiment there is provided a user-operated spotlight system forlighting a performer on a stage or performance space; the user-operatedspotlight system having an emulator adapted to communicate with at leastone spotlight, a processor connected to the emulator, and, a pluralityof controllable spotlights which are connected to the processor andwhich the plurality of controllable spotlights can be moved by a usermoving the emulator to control the plurality of spotlights.

The emulator can be embodied as a hardware module and incorporated intoan existing spotlight or follow spot, which in turn can be used tocontrol a plurality of lights where the follow spot or existingspotlight acts as a master light control with the emulator incorporatedtherein.

In a further embodiment there is provided a method of operating aspotlight system for lighting a performer on a stage or performancespace; the method including the steps of displaying an image of theperformance space on a screen and a cursor, configuring a screen cursorpositioner to be operated to move the cursor on the screen, andconnecting the screen and a plurality of controllable spotlights whichplurality of controllable spotlights can be moved by a user moving thecursor on the screen.

There is also provided a computer program comprising programinstructions for causing a computer program to carry out the abovemethod which may be embodied on a record medium, carrier signal orread-only memory.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood from the followingdescription of some embodiments thereof, given by way of example only,with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic view of a user-operated spotlight system inaccordance with the present invention, showing a screen displaying animage of a stage and the actual stage itself;

FIG. 2 is a diagrammatic view of a user-operated spotlight system inaccordance with the present invention, showing a stage and camera anglesand spotlight angles;

FIG. 3 is a diagrammatic view of a user-operated spotlight system inaccordance with the present invention, the user-operated spotlightsystem comprising a single camera and plurality of moving spotlights;

FIG. 4a is a diagrammatic view of a twin camera assembly as used in anembodiment of the present invention;

FIG. 4b is a diagrammatic view of a user-operated spotlight system inaccordance with the twin camera embodiment of FIG. 4 a, with the stageand camera angles and spotlight angles illustrated;

FIG. 5a is a diagrammatic view of a hardware setup for a user-operatedspotlight system in accordance with the twin camera embodiment of FIG. 4a;

FIG. 5b is a diagrammatic view of a software graphic user interface aswould be displayed on an operator screen for the user-operated spotlightsystem in accordance with the twin camera embodiment of FIG. 4 a; and,

FIG. 6 is a diagrammatic view of a user-operated spotlight system inaccordance with an embodiment of the present invention, theuser-operated spotlight system comprising a single camera, a singleprojector and a plurality of operator screens.

FIG. 7 illustrates one example of an emulator provided in accordancewith certain aspects disclosed herein.

FIG. 8 is a diagram illustrating an example of a hardware implementationfor a controlling apparatus in accordance with certain aspects disclosedherein.

FIG. 9 is a flowchart illustrating a method of operating a spotlightsystem for lighting a performer on a stage or performance space inaccordance with certain aspects disclosed herein.

DETAILED DESCRIPTION

The present invention relates to a user-operated spotlight systemeffected by a video camera being mounted over a stage or performancespace, at some angle, in order that the viewing angle of the cameracovers the entire stage, so that entire stage is presented to a humanoperator on a computer screen, which displays the image captured by thecamera via video stream. Therefore, a stage performer will be seen bythe operator on a computer screen. The operator is directing movinglight beams, which are referred to as light sources or spotlights also,to light the performer by placing a cursor which is also shown on thecomputer screen at the performer's feet. The present invention willreceive the cursor position on the screen and will calculate therequired amount of pan and tilt movements needed to direct the movinglights to light the stage performer at the point on the stage where thecursor is overlaying on the screen image on the stage on the computerscreen. This provides the moving lights which are controlled thefunctionality of a conventional light source. When the stage performermoves, the operator will follow the performer's feet by moving thecursor on the screen to continue to overlay on the performer's feet,using a mouse or trackpad or such similar device, thus directing themoving light to follow the performer.

In essence, the present invention converts a screen cursor position toan associated stage position. The system is initially calibrated so thata cursor overlaying a point of the image of the stage shown on thescreen will be associated with that actual position on the actual stage.Hence, the moving lights will be moved to focus their beams on thatstage position when the cursor is moved to that associated screenposition.

Referring to FIG. 1, there is provided an operator screen 100. Thescreen 100 displays an image 102 of a stage, whereby the stage islocated remotely from the screen 100. A cursor 106 is also displayed onthe screen 100. FIG. 1 also shows the stage 104 itself.

Two points A and B are shown on the stage 104. The position on the stageof point A is given by the co-ordinates (a1, a2). A moving light, in theform of a spotlight would be able to direct its beam on point A whengiven the co-ordinates (a1, a2). The associated cursor position on thescreen 100 is (x1, y1). Regarding point B, the stage positionco-ordinates are (b 1, b2) associated with (x2, y2). As can be seen, dueto the perspective view of the stage 104 on the screen 100, the valuesy1 and y2 are relative close together, when in fact the actualco-ordinates for these positions in that same axis a2 and b2 arerelative far apart. During the calibration process, the cursor positionson the screen, which in essence are the pixel positions on the screen,must be associated with the actual stage co-ordinates through thedevelopment of a translational function which will convert the cursorposition on the screen to the correct stage position. If the cursor ispositioned on the screen 100 to overlay the frontmost, leftmost point onthe stage 104, then the cursor position co-ordinates should betranslated and converted to the frontmost, leftmost stage positionco-ordinates. This conversion is carried out in a processor (not shown)which forms part of the present invention. The stage positionco-ordinates from the processor are transmitted to the plurality ofmoving lights (not shown) so as to move the moving lights to focus theirbeams on the frontmost, leftmost stage position.

It will be readily appreciated that the calibration is crucial to thepresent invention. The calibration must be completed after the camera isinstalled in a fixed position as the translational function derivedthrough the calibration is based on the pixel of the view of the screen.Any change to the camera angle or position during calibration may upsetthis derived translational function and the calibration may have to berepeated.

After calibration, and when in use, the user-operated spotlight systemallows a user, also referred to as an operator throughout thisspecification, to point the cursor 106 on the screen 100 to a positionover the image 102 of the stage 104 and cause at least some of aplurality of spotlights (not shown) which are associated to that cursor106 to move so as to illuminate that associated position on the stage104 itself.

In certain implementations, one or more cameras may be moveable, andrelocation or movement of the camera after calibration can beaccommodated. In some instances, the calibration process identifies twoor more fixed locations of a stage or performance space and therelationship between the fixed locations can be used for variouspurposes. In one example, the new or current location of a moveablecamera can be calculated based on differences in relative location oftwo or more calibrated location observed by the moveable camera. Thelocation of the moveable camera may be calculated by triangulation or bymathematical procedures. In some instances, other positional informationmay be employed to determine location of fixtures, including moveablecameras, and to adjust one or more operational parameters associatedwith the fixtures. Locational information may be obtained from globalpositioning system (GPS) receivers, proximity detectors, range-findingdevices, etc.

Referring to FIG. 2, there is provided a camera position 200 shownrelative to a stage. The camera is directed to capture a centre point202 of the stage in a central portion of the camera's field of vision.The stage is defined by corner points 204 a, 204 b, 204 c, 204 d and aperformer 206 is shown ion the stage. The field of vision of the cameramust capture at least all of the stage. The field of vision of thecamera is indicated by field of vision lines 208. The camera angle 210relative to the planar surface of the stage is shown.

A spotlight position 212 is shown such that the spotlight can be movedto illuminate the performer 206 on the stage. The focussed beam of thespotlight is indicated by lines 214.

The video camera is mounted at an angle 210, which is no greater than45°, towards the stage. This angle 210 is used by the user-operatedspotlight system in the mathematical calculation of the coordinatecalculated between the cursor position on an operator screen, which maybe given in terms of the pixel positions, and, a stage which is viewedby the video camera. Each screen pixel is calculated as a pixel that istransferred onto the stage. The camera displays the video on the screenfrom pixel (0, 0) to pixel (p1, p2). The uppermost pixel value isdependent on the screen resolution of the operator screen. Greaterresolution will ultimately allow the present invention to have a greaterand finer control of the moving lights over the stage. Duringcalibration, the video camera horizontal field of view is used and anoperator will measure the video camera angle so that each pixel on thescreen is translated as a position on the stage. For example, an upperleft pixel on the operator screen may be given as (0, 0) and this wouldbe transferred as the upper left corner 204 c of the stage. Thiscalculated position co-ordinates is a translation function which isderived for each system setup as the views, on a pixel by pixel basiswill be unique to each camera position setup.

With reference to FIG. 3, there is provided a user-operated spotlightsystem indicated generally by reference numeral 300. The user-operatedspotlight system 300 is used for lighting a performer 302. Theuser-operated spotlight system 300 comprises one camera 306 which pointsat the performer 302 on a stage. The field of view of the camera 306 isdefined by field of view lines 308 and during the setup it would beensured that the entire stage sections visible to the audience wouldalso be displayed on an operator screen 312.

A plurality of moving lights 304A, 304B, 304C which are controllable bythe user-operated spotlight system 300 are connected to a processor 310by a connection 314. In this example, in line with the DMX512 protocol,the plurality of moving lights 304A, 304B, 304C are connected in adaisy-chain arrangement. The processor 310 is connected to an operatorscreen 312. A screen cursor positioner 316 is provided to allow anoperator (not shown) to move a cursor on the screen. The co-ordinates ofthe cursor position are calculated by the processor 310 into stageposition co-ordinates which can be understood by the plurality of movinglights 304A, 304B, 304C. In one embodiment, this calculation outputsDMX512 co-ordinates which are understood by the plurality of movinglights 304A, 304B, 304C. The stage position co-ordinates are transmittedto the plurality of moving lights 304A, 304B, 304C which are thenautomatically moved to illuminate the stage position. The screen 312displays an image of the stage captured by the camera 306. In thismanner, the plurality of plurality of moving lights 304A, 304B, 304C aremoved by an operator moving the cursor on the screen 312.

The plurality of moving lights 304A, 304B, 304C must be calibratedbefore they can be used for illuminating the performer 302. Toaccomplish this preperformance calibration setup, for every movinglights separately, two points on the stage are used in a followingmanner:

-   -   using pan and tilt values, the operator will move a light beam        to any position on the stage;    -   this first position will have x and y coordinates in a stage        pixels system, and this first position is marked as T1, for        example;    -   using only tilt values, the operator will move the light beam to        another position on the stage;    -   this second position will again have x and y coordinates in the        stage pixels system, and this second position will be marked as        T2, for example;    -   the calibration procedure has now marked two points (T1, T2) on        the stage and knows the number of pan and tilt values that must        be used for the particular moving light being calibrated to move        a light beam from point T1 to point T2. It will be appreciated        more than two points can be used to increase accuracy;    -   using these known values, coordinates for a moving light neutral        position (which is when the moving light points directly down        towards the stage along its longitudinal axis; in DMX512 values,        this would be pan=128, tilt=128) are calculated as a home point        in the stage pixel coordinate system;    -   using the home point coordinates, the required pan value and        tilt value to direct the moving light at any point on the stage        is calculated.

Using this calibration procedure any number of moving lights in anyposition regarding the stage can be setup as a moving light source. Eachlight will be positioned at different location in the gantry and inareas above and surrounding the stage, so the calibration must becarried out for each light individually. Each light will have its ownmathematical function to convert pixel positions to a particular tiltand pan for that light so that it is directed towards the stageposition.

If a single camera cannot capture the stage using its field of view, atwin camera approach can be taken. As see in FIG. 4 a, there is provideda twin camera assembly indicated generally by reference numeral 400. Apair of cameras 402A, 402B are mounted on a stand 404. Looking now atFIG. 4 b, the twin camera assembly position 406 is arranged such thatthe cameras are held at a camera angle 408 from the vertical. A firstfield of view 410 for a first camera 402B and a second field of view 412for a second camera 402A are shown. These fields of view 410, 412 coverthe stage 414, which is shown in hatched lining. An overlap section 416will exist between the fields of view 410, 412. An angle 418 between thedirection of fields of view of the cameras is also shown. These anglesare used during the setup when establishing the mathematical functionsfor each of the moving lights (not shown).

Referring to FIG. 5 a, there is provided a multi-camera setup 500 whichcomprises a multi-channel viewer 506 which receives feed from at leasttwo camera feeds 502, 504. The multi-channel feed is sent to a HDMImodule 508 and is output as at least two operator screens outputs 510,512. The operator screen view is shown in FIG. 5b and comprises the twocamera feeds, which combine to give a stage view 514 with the overlap516 section. A graphic user interface with various lights controls suchas dimmers and so on can also be shown on screen I a GUI section 518.

Turning now to FIG. 6, wherein like parts previously described have beenassigned the same reference numerals, an alternative embodiment of theuser-operated spotlight system indicated generally by reference numeral600 is disclosed whereby a plurality of performers indicated generallyby reference numeral 602 are shown on a stage. The performers 602 areilluminated by a stationary projector 604 instead of a plurality ofmoving lights. The stationary projector 604 must be capable ofilluminating at point on the stage with the field of projection shownbetween field lines 606 and 608 in FIG. 6. The camera 306 captures thestage as before and a multitude of operator screens 610A, 610B, 610C,610D, 610E are operated by a separate operator each, with each operatorbeing assigned to a particular performer. The cursor position for eachof the operator screens 610A, 610B, 610C, 610D, 610E is taken andaccumulated by a processor 612 to produce an image pattern of whitespots, which act as the lights, on a black background. This generatedimage will contain the spots for each of the performers in the positionprescribed by the cursor positions on the operator screens 610A, 610B,610C, 610D, 610E. The projector 604 is then feed this information andprojects the white spots accordingly.

Instead of a projector, for multiple performers, moving lights can beused. The plurality of moving lights would be sub-divided into sets foreach of the performers, with the cursor on each of the operator screens610A, 610B, 610C, 610D, 610E being associated with one of each of thesets of the moving lights respectively.

It will be appreciated that any suitable type of light source can beused, provided the beam(s) of that light source can be moved about astage.

In certain implementations, a plurality of cameras can be controlled ina fashion similar to the control of a light source disclosed herein, anda grouping or set of cameras can be controlled in a fashion similar tothe control of sets of lights disclosed herein. In one example, a set ofcameras can be caused to focus on a particular point in space, wherethat point in space is shown on an operator screen and a cursor on thescreen can be used to change the point in space where the set of camerasare focused, and where the set of cameras may include one or morecameras. In some instances, the set of cameras may include one or moreCCTV cameras.

In certain implementations, a plurality of microphones may be controlledin a fashion similar to the control of a light source disclosed hereinand the plurality of microphones may be configured to act together tofocus in on a point in a field of interest, including a games field, orsports field, theatre stage or other performance space.

According to certain aspects of this disclosure, movable cameras may bemonitored, tracked and controlled. When a camera is stationary or ismovable but remains stationary during a performance or event, theposition of the camera in 3D space can be determined through directmeasurement, determined through calculation (based on observations forexample) and/or determined relative to other fixtures. Knowledge of theposition of a stationary camera permits calculation and calibration ofthe location of various components in a system. When component locationwithin a system is known with accuracy, movable elements within thesystem can be tracked. Such movable elements may include lights, movablecameras, projectors, scenery items, staging, performers or participants,and so on.

According to certain aspects of the disclosure, one or more movablecameras may be instrumented or configured to provide positional data toa controller or processor that can maintain a current location of eachmovable camera. The controller or processor may use calibrationinformation to process the positional data and to calculate vectorsrepresenting movements and/or a current location in 3D space. In someimplementations, the positional information can identify orientation,attitude and operational characteristics of each camera. In one example,a camera may be instrumented to provide current status periodically,after any change affecting orientation, attitude or other operationalcharacteristics of the camera, and/or in response to a query from thecontroller or processor.

In accordance with certain aspects, a camera may be configured toreceive control signals from the controller or processor that cause thecamera to track a performer. In some implementations, the locationand/or orientation of a movable camera may change when the camera istracking a performer. One or more lights may be concurrently controlledto track the performer and/or adjust the lighting of the performer basedon changes on position of the performer and/or changes in position ormode of operation of one or more cameras.

According to certain aspects, the movement of a camera may be calibratedduring setup, configuration or in response to corrections made during aperformance. In one example, calibration of a movable camera may enablethe controller or processor to generate control signals that cause themoveable camera to be moved with precision to a desired location. Insome examples, calibration of a movable camera may take intoconsideration the position and/or movement of other fixtures, includingone or more lights and one or more other cameras. In certain examples,calibration of a movable camera and/or other fixtures may be performedwhen the system is tracking a performer during a calibration process.

The manner in which a movable camera is calibrated to moving lightsand/or other fixtures may be similar to the calibration of a stationarycamera. The movable camera may be initially calibrated such that theposition of the movable camera is reliably known. The lights may besimilarly calibrated such that the position of a moving light isreliably known. A joint calibration of cameras and other fixtures may beperformed such that one or more movable cameras and other movablefixtures move in response to movement of a cursor monitored by thecontroller or processor. In one example, an operator may point thecursor at a position on a display and the position and configuration ofmovable cameras and other movable fixtures is modified to point at acorresponding physical position on a stage or performance space. Thejoint calibration of cameras and other fixtures may provide instanttracking of a movable camera simultaneously with other cameras, movinglights or movable instruments such as microphones and projectors.

In one example, a camera and light may be pointed at one or morecalibration positions, where the calibration positions have beenselected based on positions at which the light and the movable camerahave previously been calibrated. The operation of the camera and lightis known at the calibration positions and interaction with the cursorcan be calibrated in a manner that provides instant tracking of themovable camera in synchronism with other cameras, moving lights ormovable instruments such as microphones and projectors. Successfulcalibration can enable the movable cameras, lights and other fixtures toinstantly follow cursor movements.

In some implementations, operating characteristics of cameras, lights,projection systems, scenic control systems and audio systems such asmicrophones and other fixtures may be calibrated. In one example,characteristics that may be calibrated include parameters that configurezoom, aperture, focus, colour and other operating characteristics of acamera.

In another example, characteristics that may be calibrated includeparameters that configure dimmer, iris, zoom, focus, colour and otheroperating characteristics of a light fixture. Calibration can enablecontrol based upon position in the performance space or preprogramedlocations that elicit an automatic response from the system. Calibrationperformed to track the position of a single light or a plurality oflights can be used to configure a correct or desired adjustment fordimming, iris, focus and zoom values of the beam. For example, when aperformer moves further away from a light, the zoom and iris settingsmay be required to reduce in order to maintain the same beam size. Thefocus value may also be adjusted to maintain the correct focusing of thelight. The intensity of the output light, which may be controlled usinga dimmer value, is typically increased as the performer moves furtheraway from the light in order to maintain the same overall intensity ofthe beam on a performer.

The operating configuration of a camera may be adjusted to accommodatechanges in distance and beam format. Adjustment of the camera enables anoperator to control magnification of the image of a performer or scenewhen the camera is used to project captured images onto large screensfor an audience.

In some implementations, a camera, light, microphone and/or otherfixture may be instrumented to detect and communicate changes inlocation, orientation and/or configuration. In one example, sensorscoupled to the camera, light, microphone and/or other fixture maygenerate data that can be processed to generate location, orientationand/or configuration information used by a controlling device to manageaspects of a system during performance. In some instances, aninstrumented fixture may serve as a master fixture that controlsmovement of one or more other fixtures. The master fixture may be usedin place of, or in addition to a pointer that controls a cursor on adisplay. In one example, a controlling system may be configured tomonitor a master spotlight (referred to here as a master follow spot)and to cause other spotlights (follow spots) to point at the samelocation as the master follow spot. Manipulation of the master followspot may cause corresponding manipulations of any number of fixtures,including movable cameras, movable lights, projectors, scenic controls,performer flying systems, etc.

A fixture may be fitted with sensors, electronics, controllers,processors, communication devices and/or other components that enablethe fixture to operate as a master fixture. In various examples, aspotlight, microphone system or camera may be operable as a masterfixture. In certain examples, the master fixture may be an emulator thatcan be manipulated by an operator to control multiple fixtures during aperformance or show. The emulator may be mounted on a gimbal system (seeFIG. 7) and may include a processing system that function as acontroller. In some examples, the emulator may be constructed from anon-functional or mock-up fixture (light, camera) that can bemanipulated by an operator to control multiple fixtures during aperformance or show. In some instances, the master fixture may becalibrated with a cursor that controls a pointer on a display screen. Inone example, a calibration is accomplished using a follow spot beam andthe pointer on the display screen, other fixtures can be calibrated tomove in correspondence with the master follow spot.

FIG. 7 illustrates one example of an emulator apparatus 700 that may beprovided in accordance with certain aspects disclosed herein. Theemulator apparatus 700 in the example includes an enclosure 702 mountedon a gimbal system 704 that allows the enclosure to move inthree-dimensional space. In the illustrated example, the enclosure 702is mounted on a gimbal system 704 that enables rotation 710 around avertical axis (pan) and rotation 712 around a horizontal axis (tilt). Inother examples, the enclosure 702 may be mounted on a light fixture,camera, microphone system or the like using a bracket or other fasteningdevice. When mounted using a bracket, the bracket may be configured toalign or orient the enclosure 702 as needed or desired. In someimplementations, the enclosure may be mounted on a follow spot, cameraor other stationary or moveable fixture or device.

The enclosure 702 may house processing circuits, sensors, communicationdevices, etc., configured to support calibration and control of alighting system and/or one or more cameras. The enclosure 702 mayinclude or have an attached display 706 and/or one or more control inputbuttons 708. The display may include a graphical display capable ofproviding a video image, an alphanumeric display, one or more indicatorlamps, or some combination thereof. In one example, the enclosure 702 ispart of, or includes a tablet computer configured to perform one or morefunctions disclosed herein.

The emulator apparatus 700 may be deployed in a system the control oneof more lights. The emulator apparatus 700 may be mounted, fitted to, orotherwise incorporated in a follow spot. The emulator apparatus 700 maybe configured to move in a manner that emulates a traditional followspot. The emulator apparatus 700 may include a processing circuit orother electronics configured to move a cursor on a display in responseto movements of the emulator. An example of a processing circuit 802 isillustrated in FIG. 8. In some instances, a computer mouse, trackpad orother pointer configured to move the cursor on the display may serve asan emulator.

In one example, the emulator apparatus 700 may be attached to anytraditional follow spot, and permits a user to use the resulting masterfollow spot to control one or more moving lights or moving mirror typelights. the emulator apparatus 700 may provide the same type of controloutput as a mouse-based system and may operate to move a pointer on ascreen. The pointer may be displayed as a cursor or icon, for example.The pointer identifies a point in space that can be mathematicallyrepresented. Movements and adjustments of lighting systems, audiosystem, and/or camera systems may be calculated and initiated usingprocessing circuits provided in the emulator apparatus 700.

Control of lighting systems, audio system, and/or camera systems may beautomated. Automated control of a moving light system may include thecalculation and setting of parameters, such as dimmer, iris, focus andzoom setting. For example, various parameters that configure operationof a light fixture or system may be automatically adjusted when a lightfixture moves such that the size, intensity and focus characteristics ofa spot of light incident on a performer or location in a performancespace is unchanged after movement. In the latter example, beam size,brightness, focus, iris, zoom and/or any other operational parameterassociated the light fixture may be automatically controlled based oninformation obtained during calibration.

In some implementations, a camera can be fixed or stationary. The cameramay be operated to pan and tilt automatically in response to movement ofa mouse or emulator. In some instances, the pan and tilt of a moveablecamera may be controlled by a remote device that has equal planes ofmovement in pan and tilt. Focus, aperture, zoom, sensitivity and/or anyother operational parameter of the camera may be adjusted as the pan andtilt of the moveable camera is adjusted. Furthermore, Focus, aperture,zoom, sensitivity and/or any other operational parameter of the cameramay be adjusted as the beam size, brightness, focus, iris, zoom and/orany other operational parameter of one or more lighting fixtures ismodified.

FIG. 8 is a diagram illustrating an example of a hardware implementationfor an apparatus 800 employing a processing circuit 802. The apparatus800 may be used for calibrating, monitoring, configuring and controllingmovement of cameras, lights, audio and other fixtures. The processingcircuit typically has a processor 816 that may include one or moremicroprocessor, microcontroller, digital signal processor, sequencer orstate machine. The processing circuit 802 may be implemented with a busarchitecture, represented generally by the bus 810. The bus 810 mayinclude any number of interconnecting buses and bridges depending on thespecific application of the processing circuit 802 and the overalldesign constraints. The bus 810 links together various circuitsincluding one or more processors and/or hardware modules, represented bythe processor 816, the modules or circuits 804, 806 and 808,communication interface circuits 812, and the processor-readable storagemedium 818. The bus 810 may also link various other circuits such astiming sources, peripherals, voltage regulators, and power managementcircuits, which are well known in the art, and therefore, will not bedescribed any further.

The processor 816 is responsible for general processing, including theexecution of software stored on the processor-readable storage medium818. The software, when executed by the processor 816, causes theprocessing circuit 802 to perform the various functions described inthis disclosure for any particular apparatus. The processor-readablestorage medium 818 may also be used for storing data that is manipulatedby the processor 816 when executing software, including configuration,calibration and location information for one or more devices coupled tothe apparatus 800. The processing circuit 802 further includes at leastone of the modules 804, 806 and 808. The modules 804, 806 and 808 may beimplemented as software modules running in the processor 816,resident/stored in the processor-readable storage medium 818, one ormore hardware modules coupled to the processor 816, or some combinationthereof. The modules 804, 806 and/or 808 may include microcontrollerinstructions, state machine configuration parameters, or somecombination thereof.

In one configuration, the apparatus 800 may be configured forcontrolling calibrating and/or managing a performance. The apparatus 800may include a module and/or circuit 804 that is configured to controlthe movement of cameras, lights, audio and other fixtures and/or toconfigure operating characteristics of the cameras, lights, audio orother fixtures. The apparatus 800 may include tracking modules and/orcircuits 806 configured to monitor, identify and/or calculate thelocation of one or more cameras, lights, audio or other fixtures. Theapparatus 800 may include calibration modules and/or circuits 806configured to manage calibration of one or more cameras, lights, audioor other fixtures.

In one example, the apparatus 800 has a display system, one or morecameras, one or more controllable spotlights, a pointing device operableto move a cursor displayed on the display system and a controller. Thecontroller may be configured to cause the display system to display animage of the performance space provided by the one or more cameras, moveone or more controllable spotlights in correspondence with movement ofthe cursor displayed on the display system, and calibrate the spotlightsystem by linking one or more cursor positions on the image of theperformance space with one or more corresponding physical locations onthe performance space.

The pointing device may be implemented using a master spotlight. Themaster spotlight may be configured to communicate location informationto the controller. The location information may be derived from dataobtained from one or more sensors coupled to the master spotlight. Thecontroller may be further configured to cause one or more beams producedby the one or more controllable spotlights to converge at a physicallocation on the performance space indicated by the location information.

The controller may be configured to configure a parameter of at leastone controllable spotlight responsive to the movement of the cursordisplayed on the display system. The parameter may be a dimming value,an iris setting, a focus setting, a zoom setting or a colour controlparameter. Multiple parameters may be configured responsive to themovement of the cursor.

The controller may be configured to calibrate the spotlight system suchthat at least two cursor positions on the display system displaying theperformance space are linked with at least two physical positions on theperformance space.

The one or more cameras may include a moveable camera. The controllermay be further configured to cause the moveable camera to move incorrespondence with movement of the pointing device. The controller maybe configured to configure an operating parameter of the moveable cameraresponsive to the movement of the pointing device. The operatingparameter may be a zoom setting, aperture setting, focus setting orcolour control parameter. Multiple operating parameters may beconfigured responsive to the movement of the pointing device.

The processor-readable storage medium 818 may store instructions andother information related to the method illustrated in FIG. 9. Forexample, the processor-readable storage medium 818 may includeinstructions that cause the processing circuit 802 to display an imageof the performance space on a display system, configure a pointingdevice to be operated to move a cursor that is displayed on the displaysystem, cause the display system to display an image of the performancespace provided by the one or more cameras, cause one or morecontrollable spotlights to be moved in correspondence with movement ofthe cursor displayed on the display system, and calibrate the spotlightsystem by linking one or more cursor positions on the image of theperformance space with one or more corresponding physical locations onthe performance space. The pointing device may be implemented as afollow spot, an emulator, mouse or other device.

In certain examples, the pointing device comprises a master spotlight.The instructions may cause the processing circuit 802 to receivelocation information from the master spotlight. The location informationmay be derived from data obtained from one or more sensors coupled tothe master spotlight. Responsive to the instructions, the processingcircuit 802 may cause one or more beams produced by the one or morecontrollable spotlights to converge at a physical location on theperformance space indicated by the location information.

In some implementations, the instructions may cause the processingcircuit 802 to configure a parameter of at least one controllablespotlight responsive to the movement of the cursor displayed on thedisplay system. The parameter may be a dimming value, an iris setting, afocus setting, a zoom setting or a colour control parameter. Multipleparameters may be configured responsive to the movement of the cursor.

In some instances, the instructions may cause the processing circuit 802to calibrate the spotlight system such that at least two cursorpositions on the display system displaying the performance space arelinked with at least two physical positions on the performance space.

In certain implementations, a moveable camera is included in the one ormore cameras. The processing circuit 802 may cause the moveable camerato move in correspondence with movement of the pointing device. Theinstructions may cause the processing circuit 802 to configure anoperating parameter of the moveable camera responsive to the movement ofthe pointing device. The operating parameter may be a zoom setting,aperture setting, focus setting or colour control parameter. Multipleoperating parameters may be configured responsive to the movement of thepointing device.

FIG. 9 is a flowchart 900 illustrating a method of operating a spotlightsystem for lighting a performer on a stage or performance space inaccordance with certain aspects disclosed herein. In one example, themethod is performed by the processor 816 illustrated in FIG. 8. At block902, the processor 816 may display an image of the performance space ona display system. At block 904, the processor 816 may configure apointing device to be operated to move a cursor that is displayed on thedisplay system. The pointing device may be implemented as a follow spot,an emulator, mouse or other device. At block 906, the processor 816 maycause the display system to display an image of the performance spaceprovided by the one or more cameras. At block 908, the processor 816 maymove one or more controllable spotlights in correspondence with movementof the cursor displayed on the display system. At block 910, theprocessor may calibrate the spotlight system by linking one or morecursor positions on the image of the performance space with one or morecorresponding physical locations on the performance space.

In certain examples, the pointing device comprises a master spotlight.The processor 816 may receive location information from the masterspotlight. The location information may be derived from data obtainedfrom one or more sensors coupled to the master spotlight. The processor816 may cause one or more beams produced by the one or more controllablespotlights to converge at a physical location on the performance spaceindicated by the location information.

In some implementations, the processor 816 may configure a parameter ofat least one controllable spotlight responsive to the movement of thecursor displayed on the display system. The parameter may be a dimmingvalue, an iris setting, a focus setting, a zoom setting or a colourcontrol parameter. Multiple parameters may be configured responsive tothe movement of the cursor.

In some instances, the processor 816 may calibrate the spotlight systemsuch that at least two cursor positions on the display system displayingthe performance space are linked with at least two physical positions onthe performance space.

In certain implementations, a moveable camera is included in the one ormore cameras. The processor 816 may cause the moveable camera to move incorrespondence with movement of the pointing device. The processor 816may configure an operating parameter of the moveable camera responsiveto the movement of the pointing device. The operating parameter may be azoom setting, aperture setting, focus setting or colour controlparameter. Multiple operating parameters may be configured responsive tothe movement of the pointing device.

The terms “comprise” and “include”, and any variations thereof requiredfor grammatical reasons, are to be considered as interchangeable andaccorded the widest possible interpretation. It will be understood thatthe components shown in any of the drawings are not necessarily drawn toscale, and, like parts shown in several drawings are designated the samereference numerals. It will be further understood that features from anyof the embodiments may be combined with alternative describedembodiments, even if such a combination is not explicitly recitedhereinbefore but would be understood to be technically feasible by theperson skilled in the art.

The embodiments in the invention described with reference to thedrawings comprise a computer apparatus and/or processes performed in acomputer apparatus or processor. However, the invention also extends tocomputer programs, particularly computer programs stored on or in acarrier adapted to bring the invention into practice. The program may bein the form of source code, object code, or a code intermediate sourceand object code, such as in partially compiled form or in any other formsuitable for use in the implementation of the method according to theinvention. The carrier may comprise a storage medium such as ROM, e.g.CD ROM, or magnetic recording medium, e.g. a memory stick or hard disk.The carrier may be an electrical or optical signal which may betransmitted via an electrical or an optical cable or by radio or othermeans.

The invention is not limited to the embodiments hereinbefore describedwhich may be varied in both construction and detail.

What is claimed is:
 1. A spotlight system for tracking a performer on aperformance space, comprising: a display system; one or more cameras;one or more controllable spotlights; a pointing device operable to movea cursor displayed on the display system; and a controller configuredto: cause the display system to display an image of the performancespace provided by the one or more cameras; move one or more controllablespotlights in correspondence with movement of the cursor displayed onthe display system; and calibrate the spotlight system by linking one ormore cursor positions on the image of the performance space with one ormore corresponding physical locations on the performance space.
 2. Thesystem of claim 1, wherein the pointing device comprises a masterspotlight.
 3. The system of claim 1, wherein the pointing device isattached to a camera.
 4. The system of claim 1, wherein the pointingdevice comprises an emulator.
 5. The system of claim 1, wherein thepointing device is configured to: communicate location information tothe controller, the location information being derived from dataobtained from one or more sensors coupled to the pointing device.
 6. Thesystem of claim 5, wherein the controller is configured to: cause one ormore beams produced by the one or more controllable spotlights toconverge at a physical location on the performance space indicated bythe location information.
 7. The system of claim 1, wherein thecontroller is configured to: configure a parameter of at least onecontrollable spotlight responsive to the movement of the cursordisplayed on the display system, wherein the parameter comprises adimming value, an iris setting, a focus setting, a zoom setting or acolour control parameter.
 8. The system of claim 1, wherein thecontroller is configured to: calibrate the spotlight system such that atleast two cursor positions on the display system displaying theperformance space are linked with at least two physical positions on theperformance space.
 9. The system of claim 1, wherein the one or morecameras includes a moveable camera and the controller is configured to:cause the moveable camera to move in correspondence with movement of thepointing device.
 10. The system of claim 9, wherein the controller isconfigured to: configure an operating parameter of the moveable cameraresponsive to the movement of the pointing device, wherein the operatingparameter comprises a zoom setting, aperture setting, focus setting orcolour control parameter.
 11. A method of operating a spotlight systemfor lighting a performer on a performance space, comprising: displayingan image of the performance space on a display system; configuring apointing device to be operated to move a cursor that is displayed on thedisplay system; causing the display system to display an image of theperformance space provided by one or more cameras; moving one or morecontrollable spotlights in correspondence with movement of the cursordisplayed on the display system; and calibrating the spotlight system bylinking one or more cursor positions on the image of the performancespace with one or more corresponding physical locations on theperformance space.
 12. The method of claim 11, wherein the pointingdevice comprises a master spotlight or emulator.
 13. The method of claim11, wherein the pointing device comprises a camera.
 14. The method ofclaim 11, further comprising: receiving location information from thepointing device, the location information being derived from dataobtained from one or more sensors coupled to the pointing device. 15.The method of claim 14, further comprising: causing one or more beamsproduced by the one or more controllable spotlights to converge at aphysical location on the performance space indicated by the locationinformation.
 16. The method of claim 11, further comprising: configuringa parameter of at least one controllable spotlight responsive to themovement of the cursor displayed on the display system, wherein theparameter comprises a dimming value, an iris setting, a focus setting, azoom setting or a colour control parameter.
 17. The method of claim 11,further comprising: calibrating the spotlight system such that at leasttwo cursor positions on the display system displaying the performancespace are linked with at least two physical positions on the performancespace.
 18. The method of claim 11, wherein the one or more camerasincludes a moveable camera, further comprising: causing the moveablecamera to move in correspondence with movement of the pointing device.19. The method of claim 18, further comprising: configuring an operatingparameter of the moveable camera responsive to the movement of thepointing device, wherein the operating parameter comprises a zoomsetting, aperture setting, focus setting or colour control parameter.20. A processor-readable storage medium comprising code for: displayingan image of a performance space on a display system, wherein the imagerelates to a performer on the performance space; configuring a pointingdevice to be operated to move a cursor that is displayed on the displaysystem; causing the display system to display an image of theperformance space provided by one or more cameras; moving one or morecontrollable spotlights in correspondence with movement of the cursordisplayed on the display system; and calibrating the one or morecontrollable spotlights by linking one or more cursor positions on theimage of the performance space with one or more corresponding physicallocations on the performance space.